Apparatus for and process of making synthetic products



G. H. ELLIS Feb. 11, 1936.

- APPARATUS FOR AND PROCESS OF MAKING SYNTHETIC PRODUCTS Filed Jan. 13,1934 2 Sheets-Sheet l Inventor:

rye H. Ellis Inventor-z George H. E His 2 Sheets-Sheet? G. H. ELLISFiled Jan. 13, 1954 APPARATUS FOR AND PROCESS OF MAKING SYNTHETICPRODUCTS Feb. 11; 1936.

Patented Feb. ll, 1936 PATENT OFFICE APPARATUSFOR AND PROCESS OF MAK-ING SYNTHETIC PRODUCTS George 11. Ellis, St. Paul, Minn.,assignor to TheInsulite Company, Minneapolis, Minn., a cor-- .poration of MinnesotaApplication January 13, 1934, Serial No. 706,555

22 Claim.

This invention relates generally to an apparatus for and process ofmaking synthetic products which are hard, stifi, board like andparticularly to board like bodies which have high tensile strength,which are highly non-water absorbent and which have a small coeflicientof expansion in the presence of moisture.

Another object of the invention is in making of composition boards orsheets adapted for use in construction of buildings and for variousother purposes.

A further object of the invention is to provide an improved process offorming composition boards or sheets from fibrous pulp stock whichconsists in subjecting the fibrouspulp stock to elements to form a web,subjecting'the web to pressure to remove surplus fluid, applying heat.

and pressure to compact and unite the fibrous web, severing the webtransversely and subjecting the severed portions to cooling.

A further object is to provide an apparatus of the class describedincluding heated pressing rolls which receive the fibrous web andcompact it into a hard, stifi, water resistant body.

A further object of the invention is the production of synthetic bodieswhich are evenly colored and of a uniform thickness.

A further object of the invention is the continuous production of asheet of the type described in any desired length, width and thickness.

The invention relates to the production of hard, stiff bodies by firstforming from fibrous pulp stock a continuous web or sheet, squeezing thesurplus moisture from the web or sheet, passing the web through a drierto dry the web, passing the web through heated rolls to compact andunite the web into a homogeneous body, trimming or severing thesheetlongitudinally, severing the web into any desired length, and passingthe severed portions through cooling apparatus from which the finishedproduct is removed.

The invention also relates to the production of an endless sheet fromfibrous pulp stock, passing the fibrous sheets through squeezing rollsto remove surplus moisture, passing the wet sheet through rolls to dry,compact and unite the fibrous sheet into a hard, stiff, water resistantbody, severing the body into any desired length and width, passing thesevered portions through humldlfying and cooling means to complete theoperation.

The invention also relates to making fibrous products which will not beattacked by insects,

' fungi and the like.

In carrying out the process'water proofing material may be added to thefibrous pulp so that the finished products will have greater waterresistant qualities. The water proofing material may be either vegetableor mineral oils. The water resistant material is preferably mixed withthe fibrous pulp stock but it may be added to the 5 sheet after it isformed and so far as this process is concerned it is not material atwhat time the water resistant material is added.

And still further object of the invention is to provide an improvedmethod and apparatus by 1 which synthetic bodies may be producedefflcient-f ly, economically and continuously. By the use of theimproved method and apparatus none of the apparatus is permitted duringthe manufacture to remain idle.

'Ifdesired the hard sheet may be tempered and. the tempering materialmay be forced into the sheet by the use of heated rolls but it is' to beunderstood that the tempering may be done without the use of the heatedrolls although it has 20 been found preferable to use such rolls.

When the fibrous sheet is dried prior to pressing it has been foundhighly desirable to spray the surfaces of the sheet with water justprior to the introduction into the heated pressing rolls.

Satisfactory hard, water resistant board may be produced withoutspraying the surface of the dried sheet.

With the foregoing and other objects in view the invention consists ofthe novel construc- 30 tion, combination and arrangement of partshereinafter more specifically described and i1- lustrated in theaccompanying drawings wherein is shown embodiments of the invention andalso in the novel steps of the process herein-after to be more fullydescribed but it is to be understood that changes, variations andmodifications may be resorted to which fall within the scope of claimshereunto appended. In the accompanying drawings which illustrateembodiment of inven- 40 tion and form a. part of the specification:

Figure lie a view diagrammatically illustrating an apparatus for makingcomposition boards or sheets and includes a felting machine, squeezingrolls, drier, pressing means severing devices, hurnidifying and coolingdevices.

Figure 2 is a sectional view of the rotative pressing members withportion broken away showing a fibrous sheet passing there-through.

Figure 3 is a view of the pressing rolls, with part broken away,illustrating one means of heating.

Figure 4 is a view diagrammatically illustrating vacuum means forincorporating toxic agent into a Wet formed sheet. 66

To fully understand the advantages of the novel arrangement of theapparatus and novel steps of the process as well as the new productsreference will be made to the method and apparatus used heretofore inthe production of synthetic bodies. In theknown process of makingsyntheticproducts which are hard and stiff it is necessary to sever thewet sheet into sections and to place such severed sections in a heatedhydraulic press where they are subjected to heat and pressure for aperiod ranging from 14 to 30 minutes. The size of the product is of anecessity limited to the size of the hydraulic press.

According to the process herein-after to be more,

vegetable substance, preferably wood, the vegetable substance ismechanically disintegrated or flberized into long, coarse fibers such asare commonly used in the manufacture of insulating bodies. Although itis preferred that mechanically disintegrated material be used, highlysatisfactory results have been obtained by the use of what is commonlyknown as chemical pulp, semichemical pulp or a mixture of themechanically prepared and chemically treated pulp and/or semi-chemicallytreated pulp.

It has been found highly desirable that some binder be commingled withthe pulp before the fibrous sheet is formed, also, if an insect andfungi proof board is desired some toxic agent should be thoroughlycommingled with the pulpv stock or introduced into the sheet prior todrying.

It is preferred that the toxic agent be a creosote derivative, but it isto be understood that any suitable toxic agent may be used. The toxicagent if commingled with the pulp or added to the sheet after beingformed by vacuum means I will be thoroughly distributed through thefinished product. The fibrous pulp is formed into a relatively thicksheet depending upon the thick ness of the finished product and thesheet so formed is subjected to a squeezing device to remove the surpluswater. It is not absolutely essential that the surplus water be squeezedfrom the sheet although the efficiency of the drier is increased if thesurplus water is removed prior to the drying. The sheet after beingsubjected to the squeezing action to remove the surplus water is passedthrough a drier. The sheet when discharged from the drier may be bonedry but it is preferred that it have moisture contents ranging from /g%to 10% preferably 5 or 6%.

In one embodiment of invention here shown, there is illustrated inFigure 1, an apparatus for carrying out the improved process of makingsynthetic bodies such as boards, sheets, or the like.- This apparatus isshown comprising a suitable felting machine A, pressing or squeezingdevice B, drying device C, nozzles D for spraying the surface of thesheet, rolls E for compacting the sheet, rolls F for spreading liquid onthe surface of the sheet, heated rolls G, longitudinal trimming orcutting device H, cutting device I, for transversely severing the sheet,a humidifying chamber J and a cooling chamber K.

- by means of rolls 1.

nozzles D where the surfaces of sheet are wet.

There are a number of advantages obtained by spraying the sheet. One isthat the finished prodnot will have a highly polished, and what may betermed glass-smooth surface. The sheet then passes into the heatedrotative pressing means to compact, harden and unite the sheet into ahomogeneous body.

The surface of the rotative pressing means are maintained in a polishedand cleaned condition The sheet after leaving the pressing means passesbetween the rolls F which are so mounted and arranged in liquidcontainers Ill that they spread upon the surface of the sheet a liquidsubstance for tempering the sheet. The sheet is then passed throughheated rolls G to evenly distribute the tempering material over thesurface and cause the material to penetrate the body of the sheet. sheetis first trimmed or cut longitudinally and thereafter the sheet istransversely severed at intervals by means of cutting device E. Thesevered portions pass into a humidifying chamber where they are treatedand from this chamber they pass into a cooling device where they arethoroughly cooled and when discharged from the cooling device are readyfor shipment. The steps of humidifying and cooling may be reversed, thatsheet is to gradually compact the sheet into the pre-determinedthickness and the simultaneous application of heat and pressure causesthe fibrous material to coalesce and become welded together so that thepressed sheet is hard, stiff and homogeneous.

The exact action that takes place-while the sheet is passed between thepressing rolls is not known but the products are far superior to theproducts produced by a hydraulic press. This may be due in part to thefact that atmospheric air is not excluded from the sheet but for arelatively short time if excluded at all.

The pressing rolls may be heated by gas burners l2 as shown in Figure 2wherein the flames .impinge directly against the inner surfaces of The:.1

the rolls. The rolls may as readily be heated by electrical means or infact by any suitable means desired.

The pressure to which the sheet is subjected depends upon the desireddensity of the finished product. Pressures from 10,000 to 50,000# perfoot of width of the sheet being pressed gives very satisfactory resultsbut variations in the pressure above and below these amounts may beresorted to.

When preparing the pulp vegetable oils such as tung oil, soy bean oil,cotton seed oil may be and preferably :is commingled with the pulp or amineral oil such as petrolatum may-be commingled with the pulp. The bestresults thus far obtained have resulted from the use of to 10% of tung"oil or'soy bean oil, although it is to be understood that theinventionis not limited to the use of any particular oil but broadly comprehendsthe production of hard, stiff, water resistant, homogeneous syntheticbodies which are compacted and united by the means of heated rotativemembers.

The pressing rolls E, may be of any desired size and highly satisfactoryresults have thus far been obtained by using rolls 40". in diameter andalso rolls 60" in diameter. The pressing rolls should be heated to atemperature ranging from 300 F. to 700" F. The temperature to which therolls are heated depends in part upon the speed at which the'rolls areto be rotated, upon the qualities of the board desired and upon thepressure to which the sheet being pressed is subjected. The uniformityof color of synthetic bodies also depends upon maintaining the pressingtemperature substantially constant.

InFlgure 3 the pressing rolls 8- and 9 are disclosed as comprising drumlike members I9 and I4 having flanges I5 and I6 respectively and theseflanges are adapted to rest upon shoulders of end members l and la. Theend members in thisembodiment are constructed in the form ar spider butif the rolls are heated by steam or electrical means the ends will beclosed. The end members I1 and i8 are rigidly secured to the drummembers I 3 and H by bolts l8 or in any suitable manner.

Suitably secured to the end members I1 and I8 and extending outwardlytherefrom are shafts l9 and 29 which are supported in suitable bearings.2i and 22. The bearings 2| and 22 are supported by suitable framemembers 23. If desired additional supporting means may be provided although it is not'essential that such additional supporting means beused. The rolls are caused to rotate at the desired speed by anysuitable ,means, not shown.

Shafts l9 and have openings 24 extending therethrough and heating meansextending through such openings. In Figure 3 oil burners 25 aredisclosed as the heating means. The flames from the burners 25 areadapted to impinge against baffle plate 25 and be deflected therefromagainst the inner surfaces of the rolls. The baflle plate 26 issupported by means of rods 21. which are suitably secured to the endmembers l1 4 and I8.

To insure uniformity of thickness of the sheet I and to permit differentthicknesses of sheets to be produced means are provided for spacing therolls at the desired distance apart. This means may be mounted directlyupon the rolls themselves or it may be a separate unit. In Figure 3there is disclosed the preferred form of the device for accomplishingthis purpose.

In bearing member, 22 is threaded opening 28in which is adapted to beadjustably secured member 29 which has a thread end for cooperating withthe thread opening 28. For locking the member 29 in the adjustedposition lock-nut 30 is provided. So that a wrench can be used to adjustthe member 29 enlarged portion 3| is provided.

The bearing 2| rests directly upon the upper end of member 29. Thus whenmember 29 is adjusted to any desired position the uniformity of thesheet being pressed is insured.

So that the desired pressure on the rolls may be obtained means forapplying pressure must be provided and in Figure 3 is disclosed onemeans of obtaining this result. Made integral with a bearing 2| andextending therefrom is pin member 33. Adapted to slidably engage thispin is member 34, which secures in place the spring member 32. To permitthe pressure to be varied member 34 is provided with a threaded portion35 which extends through the frame member 23 and is adapted to cooperatewith threaded opening therein. After the desired pressure has beenobtained lock-nut 36 is secured in place. I I As shown in Figure 4 thetoxic agent may be incorporated into the wet formed sheet by vacuummeans. This may be accomplished byany desired arrangement but thearrangement disclosed in Figure 4, in which the vacuum box 31, isarranged beneath the sheet and a spray member consisting of pipes 38,having a series of apertures 39, therein. The toxic agent, such as thecoal tar product, is melted with rosin and formed into a soap. This ismixed with a suitable liquid such as water so that it may be readilysprayed upon the surface of the sheet. The vacuum being located on theopposite side of the sheet causes the toxic agent which has been sprayedin finely divided streams upon the surface of the sheet to be drawn intosuch sheet.

The temperature at which the pressing rolls are to be heated depends inpart on the qualities of the products desired, the pressure at which thesheet being pressed is subjected and the speed at which the pressingmeans are rotated.

It has been discovered that under certain con- I ditions a fibrous sheethaving certain vegetable oils disseminated therethrough that the oilwill harden, oxidize or vulcanize under the rotating of the pressingrolls at a suitable speed when a suitable temperature and pressure isused. It has also been discovered that if certain mineral oils areincorporated in a fibrous sheet and the sheet subjected to heat andpressure that the water resistant qualities of the sheet is greatlyimproved. The action of the oils is believed to be that of hardening,oxidizing or vulcanizing but whatever action takes place the qualitiesof the products produced. are far superior ,in tensile strength, waterresistance and hardness.

The sheet when discharged from the pressing rolls may be severed intothe desired length and width but it is preferred that the sheet be sub--jected to further treatment.

It is preferred that the sheet after being discharged from the pressingrolls is passed through rolls where a liquid material is applied to thesurface of the sheet. This material may be gloss oil or the like and itis applied for the purpose of tempering the sheet. To obtain the bestresults from the tempering material the sheet is passed through heatedrolls which causes the tempering material tobe evenly spread over thesurface, to penetrate and'to smooth the surface of the sheet. The sheetis then trimmed or severed longitudinally. by any suitable means andafter being trimmed or severed longitudinally is divided The syntheticproducts absorb very little mois- 'ture when stored andsuch bodiesnormally prejected to tempering operation to increase certain SerialNumber 706,556.

serve their shape but when the synthetic bodies are secured in positionas for example on a wall or otherwise exposed to atmospheric air theyabsorb moisture therefrom and sometimes expand and buckle or warp.Although in some instances the synthetic bodies will buckle or warp whennot secured in position.

Normally warping or buckling of synthetic products is due to the factthat after being secured in place they absorb moisture which causes themto expand. tBeing secured in place the expansion is restricted to acertain extentand this results in what is commonly known as warping.There have been efforts made heretofore to produce non-warpable boardsbut such efforts have proved extremely diificult to carry out or highlyunsatisfactory. When synthetic products are treated according to theprocess here-in set forth the tendency of such products to warp isreduced to a minimum. I

After the compacted sheet has been severed the severed portions arepassed into a humidifying chamber, preferably a steam chamber, wherethey absorb 5 to 9% of moisture. The severed portions are advancedthrough the humidifying chamber in a horizontal position while all thesurfaces are uniformly exposed to the humid air. The bodies whendelivered to the humidifying chamber are in a relatively hot conditionand rapidly absorb the desired amount of moisture.

After the severed portions have absorbed the desired amount of moisturethey are passed into a cooling chamber and it is preferred that suchchamber be provided with means for forcing atmospheric air therethrough.When the severed portions are discharged from the cooling chamber theyare ready for use.

The synthetic products may have a wire screen impression on one surfaceif desired and this may be accomplished by placing screen around theroller press members in a manner disclosed in my co-pending applicationfiled January 13, 1934, The sheet after being discharged from the heatedpressing rolls is subqualities, particularly the hardness of thesynthetic products. The sheet is then severed into any desireddimensions and the severed portions passed through a humidifying chamberwhich is preferably a steam chamber and thence through a cooling means.

It is to be understood that certain steps of the process may be alteredas to the sequence in which they are performed and that certain stepsmay be omitted and yet obtain synthetic products which are hard,grainless, homogeneous and highly water resistant.

If desired, vegetable oil in excess of what is required to bond orcement the-fibrous material together may be commingled with the pulp andthe oil in excess of what is required to cement the fibrous materialtogether can be utilized'to temper the board. If this method is followedadditional surface tempering material may be applied to the sheet in amanner as previously described.

proof, synthetic bodies which comprises forming a continuous sheet fromfibrous pulp stock having commin'gled therewith atoxic agent, squeezingthe sheet to remove the surplus water, drying the sheet to removesubstantially all the moisture, compacting the sheet under heat and pressure by means of rotatable members, tempering the sheet, severing thesheet transversely, passsevering the sheet transversely, passing thesevered portions through a humidifying chamber and finally passing thesheet through a; cooling means.

3. A process for producing non-warpable synthetic bodies which includesforming a; sheet from fibrous pulp stock pressing the sheet under heatand pressure and passing the sheet through a humidifying means whereinall the surfaces of the sheet are uniformly exposed to the humid air.

4. The process for producing non-warpable synthetic bodies whichcomprises forming a sheet from fibrous pulp stock, compacting the sheetunder heat and pressure and passing the sheet horizontally through ahumidifying means.

5. A process for producing non-expandable synthetic bodies whichcomprises forming a sheet from fibrous pulp stock, pressing the sheetunder heat. and pressure by means of rolls, severing the sheettransversely and passing the severed portions horizontally through ahumidifying chamber wherein all the surfaces of the severed portions areuniformly exposed to the humid air.

6. An apparatus for making synthetic products from fibrous materialwhich includes rotatable rolls for compacting and uniting the fibrousmaterial into a homogeneous body and .means for heating the rolls and.baflle plates secured within rolls and against which the heating mediumis adapted to impinge.

7. In an apparatus of the class described rotatable, hollow,'cylindricalmembers; means for internally heating said rotatable members, spring Imeans for applying pressure to the upper cylindrical members; and meansfor adjustably spacing rolls at a pre-determined distance apart, saidadjusting means operatively connected to one rotatable member andoperatively contacting another rotatable member.

8. In an apparatus of the class describedrotatable pressing rolls, meansfor adjustably spacing the rolls at a pre-determined distance apart,means for locking the adjusting means in the adjusted positions andmeans for heating the rolls to a temperature suflicient to producesynthetic products which are substantially homogeneous.

. 9. A process for the production of synthetic bodies which comprisesforming a sheet from L fibrous pulp stock having commingled therewith avegetable drying oil, passing the sheet through a drier to reduce themoisture contents to below 10%, passing the sheet through rotatablemembrs which are heated to compact and unite the sheet into ahomogeneous body, applying liquid material to the surface of the sheetwhile in a relatively hot condition, passing the sheet through heatedrolls, and finally passing the sheet throng a humidifying chamber.

10. A process for producing synthetic bodies which comprises forming asheet from fibrous pulp stock, passing the sheet through a drier, andfinally passing sheet through heated rotatable members, which are in therange of 40 to 60 inches indiameter, and wherein pressure within therange of 10 to 50 thousand pounds perioot of width is applied.

11. The process of producing hard, fungi andagent and a binder thathardens under heat and pressure.

13. The process for producing board like bodies which comprises forminga board from fibers in a water bath having commingled therewith avegetable drying oil in excess of what is required to bond the fiberstogether, drying the board, dampening the surface of the board,subjecting to simultaneous application of heat and pressure by rotatablepressing means to harden the oil and bind the fibers together wherebythe hard,

water proof board is produced,

14. A process for producing hard, stiff, water resisting panels fromfibrous pulp stock which,

includes the steps of forming a slab from pulp stock, passing the slabthrough a dryer to remove I board, drying the board to removesubstantially a1l,the moisture, dampening the major surfaces of' theboard, and simultaneously heating and pressing the board.

16. A hard, stiif, high surface strength board having greatwater-resisting properties resulting from simultaneous application ofheat and pressure to a pulp board that has a relatively dry core anddampening surfaces, the board containing a binder which sets under heatand pressure.

17. A hard, high surface strength board having great water-resistingjproperties, resulting from simultaneous application of heat andpressure to a pulp board that has been dried to remove substantially allthe moisture and the major surface dampened by water, the boardcontaining a binder of the class described.

18. A hard, high surface strength board resulting from simultaneousapplication of heat and pressure to a dry core, surface dampened, pulpboard containing a binder of the class described within the range hereinset forth.

19. A process for producing a hard, dense, synthetic board whichconsists in forming" from fibrous pulp stock a thick sheet, drying thesheet to remove substantially all the moisture, subjecting the sheet tosimultaneous application of heat and pressure by means of rotatablemembers, applying liquid material to the surfaces of the sheet andpassing the sheet between heated rotatable members. i

20. A process for producing hard, stiff, waterresisting boardscomprising forming a board from fibrous pulp stock, passing the boardthrough a dryer to remove substantially all the moisture, simultaneouslyapplying heat and pressure to the board by means of rotatable members,applying liquid material to the major surfaces of the pressed board,passing the board between heated rotatable members and cooling theboard.

21. A process for producing hard, fibrous products which includesforming a board from pulp stock having commingled therewith a binderwithin the range herein described, drying the board to removesubstantially all the moisture,

subjecting the board to simultaneous application of heat and pressure,applying liquid material to the major surfaces of the board and applyingheat and pressure. 1

22. A process for the production of synthetic bodies which comprisesforming a. thick sheet from pulp stock having commingled therewith abinder from an extraneous source, drying the sheet to removesubstantially all the moisture, subjecting the sheet to simultaneousapplication of heat and pressure, applying liquid material to thesurfaces of the pressed. sheet, and passing the sheet between heatedrotatable members.

GEORGE H. ELus.

